This invention relates to a simplified method of forming a scroll compressor.
Scroll compressors are becoming widely utilized in refrigerant compression applications. A scroll compressor includes a pair of scroll elements, each having a base and a generally spiral wrap extending from the base. The spiral wraps interfit to define compression chambers. One of the scroll members is caused to orbit relative to the other. A motor drives a shaft to cause the scroll member to orbit.
The motor and scroll unit are enclosed in a sealed housing. Within the housing there is a separator plate which separates a chamber at suction pressure, and another chamber at discharge pressure. A pressure relief valve within the separator plate is typically mounted to selectively communicate gas in the discharge pressure chamber to the suction pressure chamber. Further, the separator plate mounts a discharge tube and check valve. The compressor housing is typically closed by an end cap which is welded to the center shell. In the past, the separator plate has been welded to the end cap. Further, the pressure relief valve has been threaded into the separator plate, or, in at least one proposed compressor, resistance welded. Further, the discharge tube and check valve have typically been welded into the separator plate.
It is undesirable to perform welding operations in the vicinity of the separator plate. Weld splatter could enter into the compressor environment, and be found within the sealed housing in some percentage of the compressors having welded components.
Further, the use of a threaded pressure relief valve raises the requirement of expensive parts and complex tooling.
It is a goal of this invention to reduce the complexity of assembly of the scroll compressors. Further, while the invention is disclosed with reference to a scroll compressor, there may be application in other types of sealed compressors.
In a disclosed embodiment of this invention, the separator plate is interference fit into the end cap. In embodiments of this aspect, the separator plate may have an outer diameter which is greater than the inner diameter of the end cap. The difference in the diameters may be sufficient such that when the separator plate is forced into the end cap, it is fixed in place. In an alternative embodiment, the difference is less than this first embodiment. The second embodiment separator plate is sized to be larger than the inner diameter of the end cap for a sufficient amount that a fluid tight seal is provided at the connection, however, the separator plate may be still be moveable axially. In this embodiment, it is preferred that the separator plate rests upon a surface of the center shell to properly position and support the separator plate. Thus, the separator plate is not welded to the end cap, and no weld splatter occurs.
Further, the pressure release valve is preferably interference fit into the separator plate. In this way, no complex machining or welding need occur.
In further preferred features, the discharge tube and check valve are also interference fit within the separator plate. In this way, a subassembly of the end cap, separator plate, pressure relief valve and discharge tube may be all assembled and the entire subassembly then mounted to the scroll compressor and center shell. Since there is no welding, the present invention reduces problems with the prior art, and further reduces the complexity of forming the compressor over the prior art.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.